First measurement of the |<i>t</i>|-dependence of coherent J/ψ photonuclear production



Acharya, S, Acosta, FT, Adam, J, Adamova, D, Adler, A, Adolfsson, J, Aggarwal, MM, Rinella, G Aglieri, Agnello, M, Agrawal, N
et al (show 1018 more authors) (2021) First measurement of the |<i>t</i>|-dependence of coherent J/ψ photonuclear production. PHYSICS LETTERS B, 817. p. 136280.

Access the full-text of this item by clicking on the Open Access link.

Abstract

The first measurement of the cross section for coherent J/ψ photoproduction as a function of |t|, the square of the momentum transferred between the incoming and outgoing target nucleus, is presented. The data were measured with the ALICE detector in ultra-peripheral Pb–Pb collisions at a centre-of-mass energy per nucleon pair sNN=5.02TeV with the J/ψ produced in the central rapidity region |y|<0.8, which corresponds to the small Bjorken-x range (0.3−1.4)×10−3. The measured |t|-dependence is not described by computations based only on the Pb nuclear form factor, while the photonuclear cross section is better reproduced by models including shadowing according to the leading-twist approximation, or gluon-saturation effects from the impact-parameter dependent Balitsky–Kovchegov equation. These new results are therefore a valid tool to constrain the relevant model parameters and to investigate the transverse gluonic structure at very low Bjorken-x.

Item Type: Article
Divisions: Faculty of Science and Engineering > School of Physical Sciences
Depositing User: Symplectic Admin
Date Deposited: 14 Dec 2021 16:58
Last Modified: 16 Oct 2023 19:20
DOI: 10.1016/j.physletb.2021.136280
Open Access URL: https://www.sciencedirect.com/science/article/pii/...
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3145365